What are formed when waves cut holes into weak rock along the base of sea cliffs?

When waves cut holes into weak rock along the base of sea cliffs, they create features known as sea caves. Over time, continued erosion can cause these caves to enlarge and potentially lead to the formation of arches if the cave expands through to the other side of the cliff. Eventually, if the arch collapses, it can result in isolated rock formations called sea stacks.